ANGLES 1 revolution = 360° = 2π rad = 400 grad = 6400 mil POLYGONS Perimeter of Regular Polygon P = sn Area of Regular Polygon π A = π π·π or No apothem but there is a number of sides and measures of one side, use : A= ππ π πππ° π πππ§( ) π where s = A = π+π+π π √π π π π PARALLELOGRAM P = 2a + 2b A = bh A = abSINπ½ RHOMBUS P = 4a π π A = π¨π© A = bh APOTHEM of Regular Polygon a= π πππ° π πππ§( ) π Numbers of Diagonals in a Polygon π d = π (π − π) Numbers of Triangles formed by Diagonals drawn through the same vertex t = n-2 A = abSINπ½ ππ ππ π π a = √( )^π + ( )^π ππ π½ = π πππ−π ( ) ππ RECTANGLE P= 2L + 2W A = LW SQUARE CENTRAL Angle in a Polygon ∅π = πππ° π P=4b Each Interior Angle of a Polygon A=π 2 TRAPEZOID π−π )180° π ∅π° = ( 1 Sum of Interior Angle π°πΊ = (n-2)180° A=2(b1 +b2) h A= mh m= π1+π2 2 TRIANGLE CIRCLE Area of Triangle A π = π ππ π A = πab sinθ A =√π(π − π)(π − π)(π − π) Circumference = 2ππ or ππ Area = 2ππ 2 D = 2r S= arc length S= rπ P = 2r+s 1 2 A = π2π